Density functional study of AlBn clusters for n = 1–14

Density functional theory (DFT) B3LYP at 6-311++G(d,p) level is employed to optimize the structures of AlBn (n = 1–14) microclusters. Analysis of the energetic and structural stability of these clusters and their various isomers are presented. Total and binding energies of the clusters have been calculated. Their harmonic frequencies, point symmetries, and the highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO–LUMO) energy gaps have been determined. Results are evaluated by comparing to the previous similar works.

Research highlights▶ A single doped Al atom hardly affects the shape of the host boron clusters. ▶ Further investigation may be needed to realize the truth of that the planar/quasi-planar metal-boron is relatively more stable than any 3D isomers. ▶ The AlB8, AlB11 and AlB13 clusters are the magic sizes, i.e., these clusters possess relatively high stability among the AlBn clusters for up to n = 14. ▶ HOMO–LUMO gaps demonstrate the relatively higher chemical hardnesses at the AlB8, AlB11 and AlB13 clusters. ▶ Ionization energy calculations show that AlB9 also has chemical hardness.